Effect of environmental humidity and coating on aroma transfer through treated papers

Coupled transfers of aroma compounds and water vapour were investigated by varying the relative humidity gradient of storage (50% or 90%) of two paper packaging at 25 °C. These papers differed in their coating surface: both were identically impregnated then supercalendered, and only one was twice coated on both sides with a synthetic barrier substance. Permeability and solubility coefficients were determined. The coating treatment was more effective to decrease the permeabilities of water vapour and ethyl ester than the effect of RH. On the contrary, the RH modified the water content of the treated papers and affected more strongly their permeability and solubility to cis-3-hexenol and benzaldehyde. The cis-3-hexenol transfer through the non-coated paper and the benzaldehyde transfer through the coated paper decreased due to a probable competition with sorbed water although it increases for the cis-3-hexenol of a plasticisation phenomenon.